You’ve trudged up flight after flight in a replica of a Mayan tower only to climb into a small trough, helpless on an inner tube, legs sprawled as you look into nothing but darkness. You give yourself a shove, and this is where the Leap of Faith water ride at Atlantis in Paradise Island, Bahamas, gets its name. Gliding on a thin layer of water, you immediately plummet into daylight and what feels like a pure vertical fall. The 60-foot drop seems to take forever, even as you plunge at breakneck speed. Alas, prayers to end the descent are answered only by more terror. Nearly horizontal now, you find yourself lazing through a transparent tube in a tank full of sharks. The wild ride only comes to an end when you are unceremoniously dumped in a wading pool, dazed, but unharmed and ready for another.

The world of waterslides has been keeping thrill seekers wet and cool, but white hot with excitement, since the 1940s. Just as with roller coasters, the creation of waterslides is a constantly evolving science/art that adds new twists, speeds and feelings of dread every season. New wrinkles like funnels that have you oscillating back and forth (The Triple Twist, Great Wolf Lodge, Ohio) compete with world-record holders like the tallest (130 feet, Summit Plummet, Blizzard Beach, Florida), the longest (Mammoth, Holiday World & Splashin’ Safari, Indiana) and the largest overall water park (49 slides, Noah’s Ark Family Park, Wisconsin).

Unlike a roller coaster you are not strapped into a cart, but brave the ride on a tube, a mat or the seat of your pants. The first waterslides relied almost entirely on gravity and audience participation (you propelled yourself up a tower). Mother Nature then took over to get you down (with the aid of a pump constantly circulating water through to reduce friction). Now new innovations include linear-induction motors, which are capable of propelling you to the summit, and the water coaster, which uses a pump to push you uphill in the inclined portion of a slide.

Of course, if you don’t feature reaching speeds of 35 feet a second or enduring wedgie-inducing g-forces, you can always opt for the Atlantis’s Lazy River tube ride. You putt along at a snail’s pace through a tropical landscape—unless you get in the wrong stream and into extreme rapids powered by the master blaster. Oops.